enna 
66 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 
grape root-worm and from severe pruning in the spring. For this 
reason it might be urged by some that this experiment was not a fair 
test of the efficacy of a poison spray, because, it is said, beetles desert 
vineyards in this condition for those having a dense foliage. That 
there were a large number of beetles present, however, is shown by 
the heavy deposition of eggs in the untreated check, even though the 
foliage was light. 
SPRAYING EXPERIMENT IN A NEWLY INFESTED VINEYARD. 
Since a part of the campaign against this pest is to determine if 
thorough and timely spraying, conducted for a series of years, will 
prevent the deterioration of thrifty vineyards but recently infested, 
an experiment was planned in another vineyard. This vineyard is 
20 years old, on gravel soil, making a good growth of canes and luxu- 
riant foliage. It is infested with the grape root-worm, but is not yet 
showing evidence of deterioration. The block contains about 6 acres; 
1 acre was left unsprayed for check and the method of examination 
to determine results was the same as in the preceding experiment. 
The following table gives the record of egg deposition in this block, 
as a result of the spray applications: 
TABLE III.—Showing egg deposition on sprayed and check plats. 
CHECK (UNSPRAYED) PLAT. 
hee : Esti- Average num- 
| Number of egg clusters found. 
Disites oft): vapen vosaene ‘ ae mated | Num- | Num- |_ ber of eggs. 
applica- eae sea ber of | ber of PE Tc Ss 
tion. i : f er of | vines. | canes. er er 
Large: | oy | Small. | Total. eggs. sinieen canes 
JANIE MSt 22 so. oe | 52 | 136 | 213 401 | 8,810 25 69 | 352.4 | 127.67 
SPRAYED PLATS. 
Formula: 5 pounds blue vitriol (copper sutphate), 5 pounds lime, 3 pounds arsenate of lead, 
50 gallons water. 
PLATNO.1. - 
a 23. _|}August 2 ye 4 13 13| 30] 720 25 72| 28.8| 10 
PLAT NO.2. 
sale par) |PAUBUsL Oe 4 19 20 43 | 970 25 61| 381] 15.9 
METHODS OF RECORDING RESULTS. 
The figures on egg deposition given in the tables above were ob- 
tained by carefully removing all of the loose bark from the bearing 
canes and the trunks of 25 consecutive vines, and recording the num- 
ber of egg clusters found. Since the egg clusters varied in size, they 
were classified—after the eggs in a large number of clusters had been 
counted to ascertain the actual number—as large, when containing 50 
62>) ee 
